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2 years ago

Ed is 7 years older than Ted. Ed’s age is also 3/4 times Ted’s age. How old are Ed and Ted?

1 answer:

7 0

Let Ted be x.

Ed is 7 years older = x + 7

Ed = (3/4)Ted

(x + 7) = (3/4)x

x + 7 = 3x/4

x - 3x/4 = -7

x/4 = -7

x = -28, Ted = -28 years.

(x + 7) = -28 + 7 = -21, Ed = -21 years

Goodness. We had negative numbers for the ages, well does that make sense? No it doesn't.

Our answer is correct. But the sense in the question is lacking. The question has been wrongly set.

<span>We might assume negative ages to mean before they came into the world, before birth! </span>

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Find the slope of the line on the graph write your answer as a fraction or a whole number not a mixed number or decimal.

Scorpion4ik [409]

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Step-by-step explanation:

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1 year ago

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Step-by-step explanation:

Given, Tim and Jim are working on a school project together.

Tim takes 10 hours to complete the school project.

If Jim worked alone, it would take him 15 hours

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Then, $\dfrac{1}{t}=\dfrac{1}{\text{Time taken by Tim}}+\dfrac{1}{\text{Time taken by jim}}$

$\Rightarrow\ \dfrac{1}{t}=\dfrac{1}{10}+\dfrac{1}{15}\\\\\Rightarrow\ \dfrac{1}{t}=\dfrac{3+2}{30}=\dfrac{5}{30}\\\\\Rightarrow\dfrac{1}{t}=\dfrac{1}{6}\\\\\Rightarrow t=6$

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1 year ago

Write the definition of a right angle in BICONDITIONAL form.*

VARVARA [1.3K]

Answer:

A biconditional statement is a combination of a conditional statement and its converse written in the if and only if form. Two line segments are congruent if and only if they are of equal length. ... A biconditional is true if and only if both the conditionals are true. there??

Step-by-step explanation:

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1 year ago

Julia is standing 2 feet away from a lamppost. If she casts a shadow of 5 feet and the light makes a 20° angle relative to the g

givi [52]

Answer:

2.5477 feet

Step-by-step explanation:

Refer the image attached to understand my solution.

BC = height of lamppost.

DE = Julia

AD = shadow of Julia

BD = 2 feet. AD = 5 feet

BA = BD + AD

= 2 + 5 = 7 feet

In ΔABC

tan 20° = $\frac{BC}{BA} = \frac{BC}{7}$

BC = 7 * tan 20°

BC = 2.5477 feet

SO the height of lamppost = 2.5477 feet

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1 year ago

A human resources manager keeps a record of how many years each employee at a large company has been working in their current ro

REY [17]

Answer:

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Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal probability distribution

When the distribution is normal, we use the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

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The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

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